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1 /*
2  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that: (1) source code distributions
7  * retain the above copyright notice and this paragraph in its entirety, (2)
8  * distributions including binary code include the above copyright notice and
9  * this paragraph in its entirety in the documentation or other materials
10  * provided with the distribution, and (3) all advertising materials mentioning
11  * features or use of this software display the following acknowledgement:
12  * ``This product includes software developed by the University of California,
13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14  * the University nor the names of its contributors may be used to endorse
15  * or promote products derived from this software without specific prior
16  * written permission.
17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20  */
21 
22 #ifndef lint
23 static const char rcsid[] _U_ =
24     "@(#) $Header: /tcpdump/master/tcpdump/print-ip.c,v 1.149.2.9 2007/09/14 01:30:02 guy Exp $ (LBL)";
25 #endif
26 
27 #ifdef HAVE_CONFIG_H
28 #include "config.h"
29 #endif
30 
31 #include <tcpdump-stdinc.h>
32 
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36 
37 #include "addrtoname.h"
38 #include "interface.h"
39 #include "extract.h"			/* must come after interface.h */
40 
41 #include "ip.h"
42 #include "ipproto.h"
43 
44 struct tok ip_option_values[] = {
45     { IPOPT_EOL, "EOL" },
46     { IPOPT_NOP, "NOP" },
47     { IPOPT_TS, "timestamp" },
48     { IPOPT_SECURITY, "security" },
49     { IPOPT_RR, "RR" },
50     { IPOPT_SSRR, "SSRR" },
51     { IPOPT_LSRR, "LSRR" },
52     { IPOPT_RA, "RA" },
53     { IPOPT_RFC1393, "traceroute" },
54     { 0, NULL }
55 };
56 
57 /*
58  * print the recorded route in an IP RR, LSRR or SSRR option.
59  */
60 static void
ip_printroute(register const u_char * cp,u_int length)61 ip_printroute(register const u_char *cp, u_int length)
62 {
63 	register u_int ptr;
64 	register u_int len;
65 
66 	if (length < 3) {
67 		printf(" [bad length %u]", length);
68 		return;
69 	}
70 	if ((length + 1) & 3)
71 		printf(" [bad length %u]", length);
72 	ptr = cp[2] - 1;
73 	if (ptr < 3 || ((ptr + 1) & 3) || ptr > length + 1)
74 		printf(" [bad ptr %u]", cp[2]);
75 
76 	for (len = 3; len < length; len += 4) {
77 		printf(" %s", ipaddr_string(&cp[len]));
78                 if (ptr > len)
79                         printf(",");
80 	}
81 }
82 
83 /*
84  * If source-routing is present and valid, return the final destination.
85  * Otherwise, return IP destination.
86  *
87  * This is used for UDP and TCP pseudo-header in the checksum
88  * calculation.
89  */
90 u_int32_t
ip_finddst(const struct ip * ip)91 ip_finddst(const struct ip *ip)
92 {
93 	int length;
94 	int len;
95 	const u_char *cp;
96 	u_int32_t retval;
97 
98 	cp = (const u_char *)(ip + 1);
99 	length = (IP_HL(ip) << 2) - sizeof(struct ip);
100 
101 	for (; length > 0; cp += len, length -= len) {
102 		int tt;
103 
104 		TCHECK(*cp);
105 		tt = *cp;
106 		if (tt == IPOPT_EOL)
107 			break;
108 		else if (tt == IPOPT_NOP)
109 			len = 1;
110 		else {
111 			TCHECK(cp[1]);
112 			len = cp[1];
113 			if (len < 2)
114 				break;
115 		}
116 		TCHECK2(*cp, len);
117 		switch (tt) {
118 
119 		case IPOPT_SSRR:
120 		case IPOPT_LSRR:
121 			if (len < 7)
122 				break;
123 			memcpy(&retval, cp + len - 4, 4);
124 			return retval;
125 		}
126 	}
127 trunc:
128 	memcpy(&retval, &ip->ip_dst.s_addr, sizeof(u_int32_t));
129 	return retval;
130 }
131 
132 static void
ip_printts(register const u_char * cp,u_int length)133 ip_printts(register const u_char *cp, u_int length)
134 {
135 	register u_int ptr;
136 	register u_int len;
137 	int hoplen;
138 	const char *type;
139 
140 	if (length < 4) {
141 		printf("[bad length %u]", length);
142 		return;
143 	}
144 	printf(" TS{");
145 	hoplen = ((cp[3]&0xF) != IPOPT_TS_TSONLY) ? 8 : 4;
146 	if ((length - 4) & (hoplen-1))
147 		printf("[bad length %u]", length);
148 	ptr = cp[2] - 1;
149 	len = 0;
150 	if (ptr < 4 || ((ptr - 4) & (hoplen-1)) || ptr > length + 1)
151 		printf("[bad ptr %u]", cp[2]);
152 	switch (cp[3]&0xF) {
153 	case IPOPT_TS_TSONLY:
154 		printf("TSONLY");
155 		break;
156 	case IPOPT_TS_TSANDADDR:
157 		printf("TS+ADDR");
158 		break;
159 	/*
160 	 * prespecified should really be 3, but some ones might send 2
161 	 * instead, and the IPOPT_TS_PRESPEC constant can apparently
162 	 * have both values, so we have to hard-code it here.
163 	 */
164 
165 	case 2:
166 		printf("PRESPEC2.0");
167 		break;
168 	case 3:			/* IPOPT_TS_PRESPEC */
169 		printf("PRESPEC");
170 		break;
171 	default:
172 		printf("[bad ts type %d]", cp[3]&0xF);
173 		goto done;
174 	}
175 
176 	type = " ";
177 	for (len = 4; len < length; len += hoplen) {
178 		if (ptr == len)
179 			type = " ^ ";
180 		printf("%s%d@%s", type, EXTRACT_32BITS(&cp[len+hoplen-4]),
181 		       hoplen!=8 ? "" : ipaddr_string(&cp[len]));
182 		type = " ";
183 	}
184 
185 done:
186 	printf("%s", ptr == len ? " ^ " : "");
187 
188 	if (cp[3]>>4)
189 		printf(" [%d hops not recorded]} ", cp[3]>>4);
190 	else
191 		printf("}");
192 }
193 
194 /*
195  * print IP options.
196  */
197 static void
ip_optprint(register const u_char * cp,u_int length)198 ip_optprint(register const u_char *cp, u_int length)
199 {
200 	register u_int option_len;
201 	const char *sep = "";
202 
203 	for (; length > 0; cp += option_len, length -= option_len) {
204 		u_int option_code;
205 
206 		printf("%s", sep);
207 		sep = ",";
208 
209 		TCHECK(*cp);
210 		option_code = *cp;
211 
212                 printf("%s",
213                         tok2str(ip_option_values,"unknown %u",option_code));
214 
215 		if (option_code == IPOPT_NOP ||
216                     option_code == IPOPT_EOL)
217 			option_len = 1;
218 
219 		else {
220 			TCHECK(cp[1]);
221 			option_len = cp[1];
222 			if (option_len < 2) {
223 		                printf(" [bad length %u]", option_len);
224 				return;
225 			}
226 		}
227 
228 		if (option_len > length) {
229 	                printf(" [bad length %u]", option_len);
230 			return;
231 		}
232 
233                 TCHECK2(*cp, option_len);
234 
235 		switch (option_code) {
236 		case IPOPT_EOL:
237 			return;
238 
239 		case IPOPT_TS:
240 			ip_printts(cp, option_len);
241 			break;
242 
243 		case IPOPT_RR:       /* fall through */
244 		case IPOPT_SSRR:
245 		case IPOPT_LSRR:
246 			ip_printroute(cp, option_len);
247 			break;
248 
249 		case IPOPT_RA:
250 			if (option_len < 4) {
251 				printf(" [bad length %u]", option_len);
252 				break;
253 			}
254                         TCHECK(cp[3]);
255                         if (EXTRACT_16BITS(&cp[2]) != 0)
256                             printf(" value %u", EXTRACT_16BITS(&cp[2]));
257 			break;
258 
259 		case IPOPT_NOP:       /* nothing to print - fall through */
260 		case IPOPT_SECURITY:
261 		default:
262 			break;
263 		}
264 	}
265 	return;
266 
267 trunc:
268 	printf("[|ip]");
269 }
270 
271 /*
272  * compute an IP header checksum.
273  * don't modifiy the packet.
274  */
275 u_short
in_cksum(const u_short * addr,register u_int len,int csum)276 in_cksum(const u_short *addr, register u_int len, int csum)
277 {
278 	int nleft = len;
279 	const u_short *w = addr;
280 	u_short answer;
281 	int sum = csum;
282 
283 	/*
284 	 *  Our algorithm is simple, using a 32 bit accumulator (sum),
285 	 *  we add sequential 16 bit words to it, and at the end, fold
286 	 *  back all the carry bits from the top 16 bits into the lower
287 	 *  16 bits.
288 	 */
289 	while (nleft > 1)  {
290 		sum += *w++;
291 		nleft -= 2;
292 	}
293 	if (nleft == 1)
294 		sum += htons(*(u_char *)w<<8);
295 
296 	/*
297 	 * add back carry outs from top 16 bits to low 16 bits
298 	 */
299 	sum = (sum >> 16) + (sum & 0xffff);	/* add hi 16 to low 16 */
300 	sum += (sum >> 16);			/* add carry */
301 	answer = ~sum;				/* truncate to 16 bits */
302 	return (answer);
303 }
304 
305 /*
306  * Given the host-byte-order value of the checksum field in a packet
307  * header, and the network-byte-order computed checksum of the data
308  * that the checksum covers (including the checksum itself), compute
309  * what the checksum field *should* have been.
310  */
311 u_int16_t
in_cksum_shouldbe(u_int16_t sum,u_int16_t computed_sum)312 in_cksum_shouldbe(u_int16_t sum, u_int16_t computed_sum)
313 {
314 	u_int32_t shouldbe;
315 
316 	/*
317 	 * The value that should have gone into the checksum field
318 	 * is the negative of the value gotten by summing up everything
319 	 * *but* the checksum field.
320 	 *
321 	 * We can compute that by subtracting the value of the checksum
322 	 * field from the sum of all the data in the packet, and then
323 	 * computing the negative of that value.
324 	 *
325 	 * "sum" is the value of the checksum field, and "computed_sum"
326 	 * is the negative of the sum of all the data in the packets,
327 	 * so that's -(-computed_sum - sum), or (sum + computed_sum).
328 	 *
329 	 * All the arithmetic in question is one's complement, so the
330 	 * addition must include an end-around carry; we do this by
331 	 * doing the arithmetic in 32 bits (with no sign-extension),
332 	 * and then adding the upper 16 bits of the sum, which contain
333 	 * the carry, to the lower 16 bits of the sum, and then do it
334 	 * again in case *that* sum produced a carry.
335 	 *
336 	 * As RFC 1071 notes, the checksum can be computed without
337 	 * byte-swapping the 16-bit words; summing 16-bit words
338 	 * on a big-endian machine gives a big-endian checksum, which
339 	 * can be directly stuffed into the big-endian checksum fields
340 	 * in protocol headers, and summing words on a little-endian
341 	 * machine gives a little-endian checksum, which must be
342 	 * byte-swapped before being stuffed into a big-endian checksum
343 	 * field.
344 	 *
345 	 * "computed_sum" is a network-byte-order value, so we must put
346 	 * it in host byte order before subtracting it from the
347 	 * host-byte-order value from the header; the adjusted checksum
348 	 * will be in host byte order, which is what we'll return.
349 	 */
350 	shouldbe = sum;
351 	shouldbe += ntohs(computed_sum);
352 	shouldbe = (shouldbe & 0xFFFF) + (shouldbe >> 16);
353 	shouldbe = (shouldbe & 0xFFFF) + (shouldbe >> 16);
354 	return shouldbe;
355 }
356 
357 #define IP_RES 0x8000
358 
359 static struct tok ip_frag_values[] = {
360         { IP_MF,        "+" },
361         { IP_DF,        "DF" },
362 	{ IP_RES,       "rsvd" }, /* The RFC3514 evil ;-) bit */
363         { 0,            NULL }
364 };
365 
366 struct ip_print_demux_state {
367 	const struct ip *ip;
368 	const u_char *cp;
369 	u_int   len, off;
370 	u_char  nh;
371 	int     advance;
372 };
373 
374 static void
ip_print_demux(netdissect_options * ndo,struct ip_print_demux_state * ipds)375 ip_print_demux(netdissect_options *ndo,
376 	       struct ip_print_demux_state *ipds)
377 {
378 	struct protoent *proto;
379 
380 again:
381 	switch (ipds->nh) {
382 
383 	case IPPROTO_AH:
384 		ipds->nh = *ipds->cp;
385 		ipds->advance = ah_print(ipds->cp);
386 		if (ipds->advance <= 0)
387 			break;
388 		ipds->cp += ipds->advance;
389 		ipds->len -= ipds->advance;
390 		goto again;
391 
392 	case IPPROTO_ESP:
393 	{
394 		int enh, padlen;
395 		ipds->advance = esp_print(ndo, ipds->cp, ipds->len,
396 				    (const u_char *)ipds->ip,
397 				    &enh, &padlen);
398 		if (ipds->advance <= 0)
399 			break;
400 		ipds->cp += ipds->advance;
401 		ipds->len -= ipds->advance + padlen;
402 		ipds->nh = enh & 0xff;
403 		goto again;
404 	}
405 
406 	case IPPROTO_IPCOMP:
407 	{
408 		int enh;
409 		ipds->advance = ipcomp_print(ipds->cp, &enh);
410 		if (ipds->advance <= 0)
411 			break;
412 		ipds->cp += ipds->advance;
413 		ipds->len -= ipds->advance;
414 		ipds->nh = enh & 0xff;
415 		goto again;
416 	}
417 
418 	case IPPROTO_SCTP:
419 		sctp_print(ipds->cp, (const u_char *)ipds->ip, ipds->len);
420 		break;
421 
422 	case IPPROTO_DCCP:
423 		dccp_print(ipds->cp, (const u_char *)ipds->ip, ipds->len);
424 		break;
425 
426 	case IPPROTO_TCP:
427 		/* pass on the MF bit plus the offset to detect fragments */
428 		tcp_print(ipds->cp, ipds->len, (const u_char *)ipds->ip,
429 			  ipds->off & (IP_MF|IP_OFFMASK));
430 		break;
431 
432 	case IPPROTO_UDP:
433 		/* pass on the MF bit plus the offset to detect fragments */
434 		udp_print(ipds->cp, ipds->len, (const u_char *)ipds->ip,
435 			  ipds->off & (IP_MF|IP_OFFMASK));
436 		break;
437 
438 	case IPPROTO_ICMP:
439 		/* pass on the MF bit plus the offset to detect fragments */
440 		icmp_print(ipds->cp, ipds->len, (const u_char *)ipds->ip,
441 			   ipds->off & (IP_MF|IP_OFFMASK));
442 		break;
443 
444 	case IPPROTO_PIGP:
445 		/*
446 		 * XXX - the current IANA protocol number assignments
447 		 * page lists 9 as "any private interior gateway
448 		 * (used by Cisco for their IGRP)" and 88 as
449 		 * "EIGRP" from Cisco.
450 		 *
451 		 * Recent BSD <netinet/in.h> headers define
452 		 * IP_PROTO_PIGP as 9 and IP_PROTO_IGRP as 88.
453 		 * We define IP_PROTO_PIGP as 9 and
454 		 * IP_PROTO_EIGRP as 88; those names better
455 		 * match was the current protocol number
456 		 * assignments say.
457 		 */
458 		igrp_print(ipds->cp, ipds->len, (const u_char *)ipds->ip);
459 		break;
460 
461 	case IPPROTO_EIGRP:
462 		eigrp_print(ipds->cp, ipds->len);
463 		break;
464 
465 	case IPPROTO_ND:
466 		ND_PRINT((ndo, " nd %d", ipds->len));
467 		break;
468 
469 	case IPPROTO_EGP:
470 		egp_print(ipds->cp, ipds->len);
471 		break;
472 
473 	case IPPROTO_OSPF:
474 		ospf_print(ipds->cp, ipds->len, (const u_char *)ipds->ip);
475 		break;
476 
477 	case IPPROTO_IGMP:
478 		igmp_print(ipds->cp, ipds->len);
479 		break;
480 
481 	case IPPROTO_IPV4:
482 		/* DVMRP multicast tunnel (ip-in-ip encapsulation) */
483 		ip_print(gndo, ipds->cp, ipds->len);
484 		if (! vflag) {
485 			ND_PRINT((ndo, " (ipip-proto-4)"));
486 			return;
487 		}
488 		break;
489 
490 #ifdef INET6
491 	case IPPROTO_IPV6:
492 		/* ip6-in-ip encapsulation */
493 		ip6_print(ipds->cp, ipds->len);
494 		break;
495 #endif /*INET6*/
496 
497 	case IPPROTO_RSVP:
498 		rsvp_print(ipds->cp, ipds->len);
499 		break;
500 
501 	case IPPROTO_GRE:
502 		/* do it */
503 		gre_print(ipds->cp, ipds->len);
504 		break;
505 
506 	case IPPROTO_MOBILE:
507 		mobile_print(ipds->cp, ipds->len);
508 		break;
509 
510 	case IPPROTO_PIM:
511 		pim_print(ipds->cp,  ipds->len);
512 		break;
513 
514 	case IPPROTO_VRRP:
515 		vrrp_print(ipds->cp, ipds->len, ipds->ip->ip_ttl);
516 		break;
517 
518 	case IPPROTO_PGM:
519 		pgm_print(ipds->cp, ipds->len, (const u_char *)ipds->ip);
520 		break;
521 
522 	default:
523 		if ((proto = getprotobynumber(ipds->nh)) != NULL)
524 			ND_PRINT((ndo, " %s", proto->p_name));
525 		else
526 			ND_PRINT((ndo, " ip-proto-%d", ipds->nh));
527 		ND_PRINT((ndo, " %d", ipds->len));
528 		break;
529 	}
530 }
531 
532 void
ip_print_inner(netdissect_options * ndo,const u_char * bp,u_int length,u_int nh,const u_char * bp2)533 ip_print_inner(netdissect_options *ndo,
534 	       const u_char *bp,
535 	       u_int length, u_int nh,
536 	       const u_char *bp2)
537 {
538 	struct ip_print_demux_state  ipd;
539 
540 	ipd.ip = (const struct ip *)bp2;
541 	ipd.cp = bp;
542 	ipd.len  = length;
543 	ipd.off  = 0;
544 	ipd.nh   = nh;
545 	ipd.advance = 0;
546 
547 	ip_print_demux(ndo, &ipd);
548 }
549 
550 
551 /*
552  * print an IP datagram.
553  */
554 void
ip_print(netdissect_options * ndo,const u_char * bp,u_int length)555 ip_print(netdissect_options *ndo,
556 	 const u_char *bp,
557 	 u_int length)
558 {
559 	struct ip_print_demux_state  ipd;
560 	struct ip_print_demux_state *ipds=&ipd;
561 	const u_char *ipend;
562 	u_int hlen;
563 	u_int16_t sum, ip_sum;
564 	struct protoent *proto;
565 
566 	ipds->ip = (const struct ip *)bp;
567 	if (IP_V(ipds->ip) != 4) { /* print version if != 4 */
568 	    printf("IP%u ", IP_V(ipds->ip));
569 	    if (IP_V(ipds->ip) == 6)
570 		printf(", wrong link-layer encapsulation");
571 	}
572         else if (!eflag)
573 	    printf("IP ");
574 
575 	if ((u_char *)(ipds->ip + 1) > snapend) {
576 		printf("[|ip]");
577 		return;
578 	}
579 	if (length < sizeof (struct ip)) {
580 		(void)printf("truncated-ip %u", length);
581 		return;
582 	}
583 	hlen = IP_HL(ipds->ip) * 4;
584 	if (hlen < sizeof (struct ip)) {
585 		(void)printf("bad-hlen %u", hlen);
586 		return;
587 	}
588 
589 	ipds->len = EXTRACT_16BITS(&ipds->ip->ip_len);
590 	if (length < ipds->len)
591 		(void)printf("truncated-ip - %u bytes missing! ",
592 			ipds->len - length);
593 	if (ipds->len < hlen) {
594 #ifdef GUESS_TSO
595             if (ipds->len) {
596                 (void)printf("bad-len %u", ipds->len);
597                 return;
598             }
599             else {
600                 /* we guess that it is a TSO send */
601                 ipds->len = length;
602             }
603 #else
604             (void)printf("bad-len %u", ipds->len);
605             return;
606 #endif /* GUESS_TSO */
607 	}
608 
609 	/*
610 	 * Cut off the snapshot length to the end of the IP payload.
611 	 */
612 	ipend = bp + ipds->len;
613 	if (ipend < snapend)
614 		snapend = ipend;
615 
616 	ipds->len -= hlen;
617 
618 	ipds->off = EXTRACT_16BITS(&ipds->ip->ip_off);
619 
620         if (vflag) {
621             (void)printf("(tos 0x%x", (int)ipds->ip->ip_tos);
622             /* ECN bits */
623             if (ipds->ip->ip_tos & 0x03) {
624                 switch (ipds->ip->ip_tos & 0x03) {
625                 case 1:
626                     (void)printf(",ECT(1)");
627                     break;
628                 case 2:
629                     (void)printf(",ECT(0)");
630                     break;
631                 case 3:
632                     (void)printf(",CE");
633                 }
634             }
635 
636             if (ipds->ip->ip_ttl >= 1)
637                 (void)printf(", ttl %u", ipds->ip->ip_ttl);
638 
639 	    /*
640 	     * for the firewall guys, print id, offset.
641              * On all but the last stick a "+" in the flags portion.
642 	     * For unfragmented datagrams, note the don't fragment flag.
643 	     */
644 
645 	    (void)printf(", id %u, offset %u, flags [%s], proto %s (%u)",
646                          EXTRACT_16BITS(&ipds->ip->ip_id),
647                          (ipds->off & 0x1fff) * 8,
648                          bittok2str(ip_frag_values, "none", ipds->off&0xe000),
649                          tok2str(ipproto_values,"unknown",ipds->ip->ip_p),
650                          ipds->ip->ip_p);
651 
652             (void)printf(", length %u", EXTRACT_16BITS(&ipds->ip->ip_len));
653 
654             if ((hlen - sizeof(struct ip)) > 0) {
655                 printf(", options (");
656                 ip_optprint((u_char *)(ipds->ip + 1), hlen - sizeof(struct ip));
657                 printf(")");
658             }
659 
660 	    if ((u_char *)ipds->ip + hlen <= snapend) {
661 	        sum = in_cksum((const u_short *)ipds->ip, hlen, 0);
662 		if (sum != 0) {
663 		    ip_sum = EXTRACT_16BITS(&ipds->ip->ip_sum);
664 		    (void)printf(", bad cksum %x (->%x)!", ip_sum,
665 			     in_cksum_shouldbe(ip_sum, sum));
666 		}
667 	    }
668 
669             printf(") ");
670 	}
671 
672 	/*
673 	 * If this is fragment zero, hand it to the next higher
674 	 * level protocol.
675 	 */
676 	if ((ipds->off & 0x1fff) == 0) {
677 		ipds->cp = (const u_char *)ipds->ip + hlen;
678 		ipds->nh = ipds->ip->ip_p;
679 
680 		if (ipds->nh != IPPROTO_TCP && ipds->nh != IPPROTO_UDP &&
681 		    ipds->nh != IPPROTO_SCTP && ipds->nh != IPPROTO_DCCP) {
682 			(void)printf("%s > %s: ",
683 				     ipaddr_string(&ipds->ip->ip_src),
684 				     ipaddr_string(&ipds->ip->ip_dst));
685 		}
686 		ip_print_demux(ndo, ipds);
687 	} else {
688 	    /* Ultra quiet now means that all this stuff should be suppressed */
689 	    if (qflag > 1) return;
690 
691 	    /*
692 	     * if this isn't the first frag, we're missing the
693 	     * next level protocol header.  print the ip addr
694 	     * and the protocol.
695 	     */
696 	    if (ipds->off & 0x1fff) {
697 	        (void)printf("%s > %s:", ipaddr_string(&ipds->ip->ip_src),
698 			     ipaddr_string(&ipds->ip->ip_dst));
699 		if ((proto = getprotobynumber(ipds->ip->ip_p)) != NULL)
700 		    (void)printf(" %s", proto->p_name);
701 		else
702 		    (void)printf(" ip-proto-%d", ipds->ip->ip_p);
703 	    }
704 	}
705 }
706 
707 void
ipN_print(register const u_char * bp,register u_int length)708 ipN_print(register const u_char *bp, register u_int length)
709 {
710 	struct ip *ip, hdr;
711 
712 	ip = (struct ip *)bp;
713 	if (length < 4) {
714 		(void)printf("truncated-ip %d", length);
715 		return;
716 	}
717 	memcpy (&hdr, (char *)ip, 4);
718 	switch (IP_V(&hdr)) {
719 	case 4:
720 		ip_print (gndo, bp, length);
721 		return;
722 #ifdef INET6
723 	case 6:
724 		ip6_print (bp, length);
725 		return;
726 #endif
727 	default:
728 		(void)printf("unknown ip %d", IP_V(&hdr));
729 		return;
730 	}
731 }
732 
733 /*
734  * Local Variables:
735  * c-style: whitesmith
736  * c-basic-offset: 8
737  * End:
738  */
739 
740 
741